The only thing I can think of is they thought they were likely going to a domestic call (hang up lots of yelling). As they approached, found the house all quiet, door ajar enough to see male down and some casings. Officer #321 thinks about this (initially similar) case last year of double homicide/suicide:
Chetek deaths of man, woman, daughter were murder-suicide, Barron County sheriff says
Maybe both. Shell casings outside and inside. IDK, but I can't rule it out. James shot during breach with casings landing outdoors, then perp enters (appx 5 feet?) shots Denise and those casings land inside.
IDK. Most handgun casings I'm (very) familiar with eject 1-3 feet in back of my right shoulder and off to the side 2-6 feet to the right. In other words, after firings, take 2-6 steps to the right and 1-3 steps backwards and you'll often find your pile of brass. On the rifle range, most brass is ejected the same, but some land more forward.
I think James was at the door, inside. I'm not sure if he was answering the door, trying to prevent it from being smash in, or was opening it.
I think it was kicked in, maybe shot into too. Looks like a splintered wood door removed from the hinges in that picture, the one with the white-suit investigator guy in the doorway.
Last one is toughest. I think a couple possibilities. 1) maybe all three Closs' came out to the area (kitchen, living, dining-whatever common area is around doorway/entrance) to see wtf was going on, before any gun fire started and all the perp had to do was point a firearm at Jayme and say "come here...". Or, 2) he went and found her (hiding) but only left evidence at that initial entrance area.